There have been 426 cases of mumps reported in the United States this year as of March 29, according to the US Centers for Disease Control and Prevention.
That's an increase of 275 cases in the last month. Previously, the CDC reported 151 cases of mumps as of the end of February.
Mumps is a vaccine-preventable disease that is caused by a virus. It is spread through saliva or mucus by coughing, sneezing or talking, and sharing eating utensils or cups, according to the CDC.
It can also spread when an infected person touches items or surfaces that are then touched by someone else who picks up the virus.
Outbreaks usually occur among people who have close contact, such as on college campuses and among sports teams.
Symptoms can appear 12 to 25 days after a person is infected and can include fever, headache, muscle aches, tiredness and loss of appetite. The hallmark is swollen glands under the ears that are tender. But not everyone has symptoms, especially if they are experiencing a mild case of the illness.
The best way to prevent mumps is with a vaccine. According to the CDC, the MMR (measles, mumps and rubella) vaccine is 88% effective when two doses are given.
Temple University is in the midst of an outbreak. As of March 29, "106 cases of mumps have been diagnosed among Temple students and people outside of the university over the last month," Mark Denys, the university's director of student and employee health services, said in an update to students last week.
There were more than 2,000 cases of mumps reported in the United States in 2018.